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## Nanostructured Li-ion Batteries for Electric Cars153

schliz writes "Researchers at the Delft University of Technology are developing nanostructured batteries that are expected to deliver more usage between charges, and shorter charge/discharge times, to mobile consumers within the next five years. The batteries will improve electric and hybrid vehicles, researchers say."
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## Nanostructured Li-ion Batteries for Electric Cars

• #### The first of many stories (Score:5, Insightful)

on Wednesday April 11, 2007 @01:54AM (#18685705) Journal
Battery technology will experience a sort of Moore's Law with the demand for hybrid and all-electric vehicles. This is just one of the first stories.

I'm always a bit skeptical of such items till I understand how likely it is to cause a fire in my garage while I'm sleeping or when accelerating away from a stop light. New tech is great, but means not a lot till tested in the real world.

With battery technology, the higher the density, the higher the chances of uncontrolled energy release. When it's safe and fairly cheap, then I'll be really interested.
• #### Re: (Score:3, Insightful)

Safety is only one part of the Li-ion chemistry equation. There's also cost, lifespan (which tends to be short), and energy content. There are many variants out there that promise some, but not all, of those. Get all four in one battery, and you've got a winner.
• #### Re:The first of many stories (Score:4, Funny)

on Wednesday April 11, 2007 @02:52AM (#18685967) Homepage
Yeah, I hear those Lion batteries require a lot of mametenance. I surprised the Chrysler Prowler isn't Lion powered. Though you can be sure owners of such cars will take a lot of pride in them. They don't call you King of the concrete jungle for nothing!
• #### Re:The first of many stories (Score:5, Informative)

on Wednesday April 11, 2007 @03:19AM (#18686069)
No more maintenance that any other battery. If you want to get some feedback from people that are already using these, check out this electric vehicle forum. http://endless-sphere.com/forums/ [endless-sphere.com] I think they are already ahead of what most think is possible with electric vehicle transportation.
• #### Re: (Score:3, Informative)

It's not maintenence; it's lifespan. Conventional Li-ion (as powers most laptops) are high energy density, high flammability, moderately high cost, and short lifespan. Li-ion battery lifespans are particularly frustrating because they're not very tied to charge-discharge cycles; they're much more correlated with age and temperature. As I mentioned, there are a number of Li-ion variants, some of which are already on the market. However, most of them sacrifice energy density to reduce flammability and/or
• #### Re: (Score:3, Funny)

Er... and/or *increase* lifespan. :)
• #### Re: (Score:2)

These type of guys are the ones I always point out when conspiracy theorists go off about how the oil companies are keeping electric cars from the market place.

If the electric car really is the held back panacea some nut jobs make it out to be then hobbyists would be building them and driving them everywhere. Exxon may be able to influence GM (not that I think they are) but do you think they're knocking down the doors of everybody with an arc welder and a couple volt meters in their garage?
• #### Re: (Score:2)

+1 subtle. :-)
• #### Re:The first of many stories (Score:4, Interesting)

on Wednesday April 11, 2007 @02:27AM (#18685841) Homepage Journal
Battery technology will experience a sort of Moore's Law with the demand for hybrid and all-electric vehicles. This is just one of the first stories.

Probably not. Ultra-capacitors [maxwell.com] will be hugely superior to batteries; more charge / recharge cycles by orders of magnitude, much higher current capabilities on both charge and discharge, environmentally friendly. They're just a little bit below total battery energy levels on a by weight / volume comparison right now. If and when they cross that line, batteries will become old-tech for applications like cars.

• #### Re:The first of many stories (Score:4, Insightful)

<robert_horning AT netzero DOT net> on Wednesday April 11, 2007 @02:46AM (#18685941) Homepage Journal
I will agree that there is a glimmer of hope for ultra-capacitors, but there are also some huge technical and engineering problems that will have to be overcome. They certainly don't have the energy density of batteries, and the largest problem with them is that the discharge from an ultra-capacitor is hard to deal with using normal electronics. It can be compensated for, but it isn't easy.

I also don't buy the "environmentally friendly" nature of them as well. While they may be better than NiCd batteries or the more traditional Lead-H2SO4 batteries in terms of what they will do to the environment, you can't call them a perfect solution either. The metals used in the construction of these types of capacitors have their own kind of impact on the environment just like any manufactured product.

If a "Moore's Law" were to apply to battery capacity, instead of the (presumed) 18 month half-life of procesor density and speed, it will be more like 15-20 years instead for improved energy density. While not something to ignore, you don't have to run out and buy a new battery pack every year just to keep up with changes in the battery industry. This is very hard science, using multiple meanings of that term.
• #### Re: (Score:2)

The metals used in the construction of these types of capacitors have their own kind of impact on the environment just like any manufactured product.
RECYCLE !! Jeezes ...
• #### Re:I think you missed his point entirely... (Score:2)

The Impact on the environment is in processing/refining materials to get to the desired end product.
Recycle all of the silicon you want. You're still making a heck of an impact turning raw materials into a purified silicon wafer. Same goes with any highly processed item. Energy into fabrication of materials = harm to the environment in general... I think this is what he meant by impact from the specialized metals in these caps.
• #### Re: (Score:3, Interesting)

I agree partly, i give you that extracting the raw materials can be very harmful, but the energy required shouldn't be harmful. Still, we've thrown so much material away now, should we still be short on materials ? I think much money is to be made by 'harvesting' landfills.
• #### Re:The first of many stories (Score:5, Informative)

on Wednesday April 11, 2007 @03:33AM (#18686113) Homepage Journal
They [ultracaps] certainly don't have the energy density of batteries

Actually, they're getting very close, and right now, there are projects projecting power densities three orders of magnitude higher than batteries, in the 100 KW/kg range. [mit.edu] So I don't think the current state of affairs (batteries > ultracaps) is going to obtain for very much longer.

and the largest problem with them is that the discharge from an ultra-capacitor is hard to deal with using normal electronics. It can be compensated for, but it isn't easy.

What? ultracaps have the same discharge curve as any capacitor does; the voltage drops very smoothly as the energy in the cap is dispensed. "Dealing with it" is nothing tricky at all, the technology has been in place for this for literally decades. Modern switching power supplies are *very* efficient at creating constant voltage outputs from all manner of raggedy inputs across a wide range of input voltages, if and when required. They can be engineered to be reliable and very long lasting. This is simply a non-problem. Also, ultracaps can absorb energy (for example, from regenerative braking) at a much higher rate, leading to less wasted energy. We have all manner of high-current switching devices with such low on-resistances these days as to be utterly amazing to an old-timer like me.

I also don't buy the "environmentally friendly" nature of them as well. While they may be better than NiCd batteries or the more traditional Lead-H2SO4 batteries in terms of what they will do to the environment, you can't call them a perfect solution either. The metals used in the construction of these types of capacitors have their own kind of impact on the environment just like any manufactured product.

You're just hand-waving here. Recycling is one issue, toxicity is another, corrosion is another, and all of them are far less critical for ultracaps - not to mention that the lifetime of an ultracap is so much longer (up to a quarter of a milling charge/discharge cycles, or more) than that of a battery, so it is that much more seldom that recycling becomes an issue. It really isn't reasonable to say that ultracaps pose the same kind of environmental issues that batteries do. They don't. Perfect? No. But what is?

If a "Moore's Law" were to apply to battery capacity, instead of the (presumed) 18 month half-life of procesor density and speed, it will be more like 15-20 years instead for improved energy density.

Yes, but (a) ultracaps aren't batteries at all, and (b) ultracaps are increasing in capacity at a prodigious rate, where batteries are not. Mind you, they're coming from behind, but they're a brand new technology with tons of new research driving the improvements, while batteries are not new and many, many avenues have been tried and abandoned for increasing battery capacity for exactly the reason you cite: It is hard to improve the current battery designs.

• #### Re: (Score:2)

"milling" s/b "million" in the paragraph about recycling, my apologies.

• #### Re:The first of many stories (Score:4, Insightful)

on Wednesday April 11, 2007 @03:44AM (#18686141)
Right, but you omitted the important stat from your link: their projected energy density is only 60Wh/kg, only half that of a Li-ion battery. Who really cares if the power density is much greater? Ok, so you can get an output of 100kW/kg from your ultracapacitor, but at that rate it will discharge in just over 2 seconds/kg. This is surely useful for some applications, but not for most things we currently use batteries for.
• #### Re: (Score:2)

I consider 1/2 lion capacity to be a very significant line in the sand; as I said, there is much going on in the field, and it is both new and expanding rapidly. My original post was clear: I said "probably", and I meant it. We're not there yet. But we certainly aren't "huge problems", as you characterize them. We're in the same zone, same order of magnitude, and honestly, I have every expectation that ultracaps will come out on top. They're just too much better on too many fronts, and they're so close in

• #### 6wh/KG for ultracaps vs 120wh/KG for lithium. (Score:2)

The actual stored energy in Lithium is currently 20 TIMES greater by your own link.

Don't confuse power density with energy density. Power density is how fast you can discharge and almost a non-issue with any technology.

Energy density is how much actual energy you have stored and is the key factor, that ultracaps are behind on by an order of magnitude (20 times currently).

If all the theoretical projections make it into practice ultracaps will only halfway catch up with lithiums garden variety lithiums that e
• #### No: 60wh/KG for ultracaps vs 120wh/KG for lithium. (Score:2)

The actual stored energy in Lithium is currently 20 TIMES greater by your own link.

No; you misread the article. It said that current commercial DLC's were at 6Wh/kg; then it went on to say that the technology in the paper offered 60Wh/kg, which is 1/2 LION, not 1/20th. Also 300,000 charge cycles. You just needed to read one paragraph further. I encourage you to do so.

• #### The paper is theoretical, not expirmental. (Score:2)

I have heard theoretical claims like this before. EEstor who was supposed to supply complete ultra cap systems to power electric cars last year. They still haven't offered so much as a single cell for testing. Not even a small one off.

In theory, theory and practice are the same, in practice they aren't.

Realize they are talking about a theoretical order of magnitude improvement in energy density. I would love it if true, but often such things never see the light of day when rubber meets the road.

Nowhere has
• #### Re: (Score:2)

If you are talking about the ultimate energy storage technology, it would be anti-matter. You simply can't get more power produced as quickly or have any higher energy storage, although the technology to "confine" anti-matter from interacting with normal matter in an efficient manner is centuries away from any current practical solution. And that is precisely what you are talking about here is something which is "theory" as opposed to proven devices which you can use in production equipment.

As I said in m
• #### Re: (Score:2)

Robert, your post is so filled with misconceptions I don't even know where to start. Antimatter is completely, totally, irrelevant. Diesel and gas are irrelevant because the idea here is to get off of petrochemicals as fuels. You're wrong about recharges; ultracaps can, and do, recharge as advertised. You're wrong about power sources - current can be stored locally, just as gasoline and diesel can (the "fueling station" can pull from the utility at all times, including when it isn't providing current to it

• #### Re: (Score:2)

I do question the science, as people who I respect and do understand the technologies have strong questions about it as well. Fundamental research is needed here to improve ultracaps as an energy storage technology. I'm not saying a very bright person won't ever figure it out, but it is not something that is trivial to dismiss and presume that the breakthroughs needed will be found. I have been involved with enough engineering efforts of my own to know that sometimes you do fail on some ideas... and fail
• #### Re: (Score:2)

When I can do the same thing with electric automobiles, that will have eliminated the need to use a petroleum-based vehicle completely.

You mentioned three things. (1) Range, 600 miles. This is more often quoted at 300 miles for a passenger vehicle. UCs are not there yet, but they are within reasonable distance of catching it. I again predict 3-5 years.

(2) Refueling time of ten minutes. UCs can do this at home or on the road. Not a problem. You keep mentioning this and I suspect you don't understand

• #### Re: (Score:2)

I should have put this into the other reply, but I forgot to make this point:

If you have an ultracap I can purchase right now that has the energy density of 1/2 the equivalent of a Li-ion battery, give me the link or your phone number (or that of the business selling them) that I can go to and purchase the thing. Seriously. I've heard all kinds of bluster about this and I would like to see one. Better yet if I can get one in a form factor equivalent to one of my existing batteries, but I wouldn't mind ju
• #### Re: (Score:2)

Batteries are nothing more than a controlled bomb. The difference being a battery releases energy over a much longer period of time. However, both a battery and a bomb may contain the same energy density.

I'm with you, these high density batteries give me the creeps.
• #### Re:The first of many stories (Score:4, Insightful)

on Wednesday April 11, 2007 @03:07AM (#18686027)

Batteries are nothing more than a controlled bomb.
And this is different from petrol how ?
• #### Re:The first of many stories (Score:4, Interesting)

on Wednesday April 11, 2007 @05:49AM (#18686603)
Bombs are generally devastating because they release energy quickly, not because they have a high energy density. For instance, a ton of TNT has around 4,000 MJ, and a ton of coal is around 30,000 MJ. Compare to Li-ion at 500 MJ/ton.
• #### Re:The first of many stories (Score:5, Insightful)

on Wednesday April 11, 2007 @07:02AM (#18686955) Journal

Yeah, sounds great, until you realize that gasoline (petrol) has 45 MJ per KILOGRAM - the same order of magnitude as coal, 10 times as much as TNT, and over 80 times that of the best batteries.

The reason? Things like coal and gasoline don't carry a heavy oxidizer with them. "Air-breathing" fuels will always be better than "rocket" type fuels for transportation because of the weight and storage expense of carrying both the oxidizer and the fuel on the vehicle. That's a substantial feature for "battery-like" technology to overcome for everyone who is not a short-distance commuter.

• #### Re: (Score:2)

Yeah, sounds great, until you realize that gasoline (petrol) has 45 MJ per KILOGRAM - the same order of magnitude as coal, 10 times as much as TNT, and over 80 times that of the best batteries. The reason? Things like coal and gasoline don't carry a heavy oxidizer with them. "Air-breathing" fuels will always be better than "rocket" type fuels for transportation because of the weight and storage expense of carrying both the oxidizer and the fuel on the vehicle. That's a substantial feature for "battery-like

• #### Re: (Score:3, Insightful)

"Battery technology will experience a sort of Moore's Law with the demand for hybrid and all-electric vehicles. This is just one of the first stories."

That was a common sentiment back in the early 90's when portable devices started to take off in a big way. It proved to be a stubborn problem that tended to ignore Moore's regulations and follow Murphy's code of natural conduct. After Murphy turned up the pundits started hyping fuel cells, that also proved to be a stubborn problem with no respect for Moore
• #### Re: (Score:2)

I don't think we can expect to see a battery revolution any time soon.

The thing about revolutions is that you don't usually see them coming.

• #### Re: (Score:2)

NObody expects the Spanish Inquisition!

Oh wait...
• #### Re: (Score:2)

With battery technology, the higher the density, the higher the chances of uncontrolled energy release. When it's safe and fairly cheap, then I'll be really interested.

You know what has a really high energy density (on the order of 50-100 times [wikipedia.org] that of a Li-ion battery)? Gasoline.

• #### Re: (Score:2)

yes, but gasoline tends to prevent you being really independent. Put up some solar cells, a wind-turbine or whatever, use some batteries for your electric car ... and nobody takes your ability to drive away !
• #### Re: (Score:2, Funny)

yes, but gasoline tends to prevent you being really independent. Put up some solar cells, a wind-turbine or whatever, use some batteries for your electric car ... and nobody takes your ability to drive away !

Driving back, however... :-)
• #### Super capacitors (Score:2)

Personally, I am betting that the UltraCacpacitors will kill the batteries. Two that I am intrigued with are EEStor and MIT. EEStor is horribly sketchy, but backed by KliensPerkins (a major silicon valley VC). They have a long history of backing some major players. In addition, MIT's work appears headed in the right direction. [peswiki.com] The advantage of all this, is that this would allow home owners to recharge their cars at night and then use these cars either for driving OR for powering the home. This would give u
• #### Re: (Score:2)

I agree with you, but the other side of the coin is that we really need batteries with higher energy density before electric cars actually become practical. Sure, you can propel a vehicle forward for a distance right now, but Paying 50k for a car whose batteries will only last 2 years, whose distance won't get a lot of people to the next town, and which is completely incapable of being refuelled quickly simply isn't practical.

And before anyone gives me any "You could have replacable battery packs! You could
• #### Lithium-ion is Adequate (Score:4, Interesting)

on Wednesday April 11, 2007 @08:33AM (#18687497)
I have to disagree with your leading statement. The energy density of lithium-ion batteries today is adequate for making practical electric cars. Of course more is always better, and I'm optimistic that it can be improved further -- but energy density is no longer the big sticking point that it was.

The little two-seat Tesla Roadster with a 250-mile range has been demonstrated, and multiple companies are now working on more practical four-door cars which can have a 200-mile driving range. This doesn't require any breakthroughs, and it will get you "to the next town" with very few exceptions.

The critical areas that need improvement are cost and service life. Tesla Motors are projecting a life span of five years or 100,000 miles for their carefully managed battery pack. That's much better than the two years you stated. I think with the research that is ongoing, service life will further improve over the next several years. (And GM are betting on this happening to make their Chevy Volt concept workable.)

I think the requirement that cars be "refueled quickly" is overstated. The longer the range becomes, the less you need to refuel or recharge it quickly. With a dependable 200-mile driving range between charges, and the ability to recharge overnight at home, most people won't need to stop at a charging station mid-trip all that often. If you can get the range up to about 500 miles, then rapid charging would become moot for the great majority of people. (At least speaking for myself, I don't think I've ever driven more than 300 miles in a day's time, and I wouldn't want to drive more than 500 in a day if I could possibly avoid it.)

I have looked into flywheel storage technology. It looked promising several years ago, but battery technology advanced faster and has left flywheels behind. Notable problems you have with flywheels are: energy density, energy losses while the flywheel is spinning idle, and safety concerns about its failure modes.

The Tesla Roadster is $92,000USD base. That alone puts it far out of even the price range I consider ridiculous for basic transportation,$50,000(That's the cost of a worn, but livable, house). This car, worth $92,000, won't get me to Winnipeg, in the same province I'm in, unless I make it a two day trip. It will require new batteries, even conservatively, within 5 years(So you've got$20,000 in batteries amortized over 5 years, so you're paying $4,000/yr of hazardous chemicals ripped from the earth just li • #### Re: (Score:2) You've got it all wrong, and I'll be happy to explain why. :) The Tesla Roadster starts at$92,000 which is much less than other exotic sports cars it can run with -- Porsches and Ferraris. It's not intended to be "basic transportation" and any attempt to compare its price tag with cars that are basic transportation is pointless.

The batteries don't lay down and die at the end of five years. By then the estimate is that they'll be reduced to about 80% of their original capacity -- which means even a "worn o
• #### Re: (Score:2)

Ok I'll bite on the fly wheel idea....

What kind of fly wheel are you talking about? Scale? Materials? Stored in vacuum? What kind of mass? Which plane does it spin in? How does it cope with effects of the coreolis forces?

And of course you know it would have to be stationary? Having a fly wheel with any decent level of energy storage would also have a huge resistance against turning!!

Just to throw some numbers in the air... lets say you had a 0.2m thick 1m radius disk of lead, it would weigh approximately 70
• #### Re: (Score:2)

lets say it is spinning at 120rpm (pretty fast given how heavy this thing is)

As you elude to, the energy of a flywheel is (to a good approximation): $1/2 I \omega^2$ where I is the moment of inertia (not the mass) and omega the angular speed. The mass can be surprisingly low, if it's all concentrated away from the axis of rotation. With modern materials and engineering one can obtain very high angular speeds.

There's an overview of this technology with links in the Wikipedia article on flywheel energy storage [wikipedia.org]. It's not a new idea, having been used in the 50s to power busses i

• #### Re: (Score:2)

That's the tech I was referring to. From the looks of things, if that tech could become good enough, it would represent a power source which would have an effective life as long as the vehicle itself(About 10 years, according to one manufacturer of flywheel UPS systems), could be measured exactly in terms of remaining energy, and would represent a fairly simple to contain energy source in the event of an accident(Compare flying flywheel dust to LI-ION battery or gasoline explosion).

Really, this isn't crazyh
• #### Re: (Score:3, Insightful)

Battery technology will experience a sort of Moore's Law with the demand for hybrid and all-electric vehicles.

Demand helps, but physics (and return on investment) has limits. If technological progress (like we experienced with semiconductors) depended only on demand, then the energy market would have experienced a revolution long ago. Instead, we're still using fossil fuels and copper wire -- technologies that are at least a century old. We also still have cancer, AIDS, people dying of the flu, I can still
• #### Patented to Death? (Score:4, Interesting)

on Wednesday April 11, 2007 @02:24AM (#18685819) Homepage Journal
Will this patent monopoly on the new tech be used to kill it, just like NiMH batteries were prevented from powering cars [google.com] by the car and oil corporations?
• #### Re: (Score:2)

Is Chevron really the problem?

Or is it the 30-80 Wh/kg?
And the long recharge times.
And the cold weather performance. (specifically: the lack thereof)

But hey: NiMH's cheap, right?
Which probably explains why so many hybrids have NiMH battery packs. (Toyota Prius, Saturn Aura, etc)

So I'm not sure how you can intimate that Chevron is suppressing NiMH technology in cars, when it's already there in all the applications that don't rely solely upon the battery pack. (i.e. hybrids)
• #### Re: (Score:2)

Chevron refusing to license the patent prevented engineers from tweaking those problems, or putting out early-adopter models which would have funded innovation (perhaps beyond the patented NiMH). It took a long time for those first hybrids to use their battery tech. Without the patent suppression, we'd be a few years closer to 10x efficient vehicle energy and possibly 100x efficient pollution reduction. Which is precious time as we speed towards the oil peak and the Greenhouse tipping points.
• #### Re: (Score:2)

There's plenty of NiMH solutions that didn't and don't involve Chevron's tech.
If Chevron's patents were the only stumbling block, someone would have worked around it. Companies design around each other's patents as a matter of course.

NiMH technology is simply fundamentally unsuited to BEVs and Chevron's patents didn't change that.

If Chevron had licensed, maybe their NiMH batteries would be a bit better. But that still wouldn't make them good enough to run BEVs and even without Chevron's licenses NiMH was
• #### Re: (Score:2)

What we need more of is science.

Statistics from Wikipedia

Lithium Ion Batteries:
Battery specifications
Energy/weight 160 Wh/kg
Energy/size 270 Wh/L
Power/weight 1800 W/kg
Charge/discharge efficiency 99.9%[1]
Energy/consumer-price 2.8 Wh/US$Self-discharge rate 5%-10%/month Time durability (24-36) months Cycle durability 1200 cycles Nominal Cell Voltage 3.6 V Charge temperature interval Nickel Metal Hydride batteries Battery specifications Energy/weight 30-80 Wh/kg Energy/size 140-300 Wh/L Power/weight 250-1000 W/kg Charge/d • #### Re: (Score:2) This is a documented conspiracy, to which I linked amply, to suppress a tech that was ready for deployment, but denied to the industry. There are better techs, but that didn't stop gasoline from being the choice for a century. Your inadequate argument turned obnoxious for no reason. I'm no "arts student". You're an asshole, and a wrong asshole, too. Goodbye. • #### it's explosively fast (Score:5, Funny) on Wednesday April 11, 2007 @02:29AM (#18685849) Homepage batteries that are expected to deliver more usage between charges, and shorter charge/discharge times I believe Sony has perfected the battery with the absolute fastest discharge time. I don't see how this can compete. • #### Re: (Score:3, Funny) Actually they have reduced the discharge time to milliseconds. That's the good news, the bad news instead of rating the discharge in volts they rate them in megatons. • #### What's wrong with... (Score:3, Informative) on Wednesday April 11, 2007 @02:37AM (#18685883) Homepage Journal Lead Acid batteries? They have good energy density and can deliver considerable voltage for their size, and we've been using them for a very long time. It seems to me that perhaps someone should try researching different formulas for the acid and the chemistry of the plates. Sure, they're heavy and there's always the danger of a rupture but they are good at doing what batteries are supposed to do, storing and releasing electricity. LK • #### Re: (Score:2) Where did you get the idea that lead-acid batteries have good energy density? • #### Re:What's wrong with... (Score:5, Informative) by Anonymous Coward on Wednesday April 11, 2007 @02:47AM (#18685945) Lead-acid batteries are a lot worse in comparison... Lead-acid batteries [wikipedia.org] Energy/weight 30-40 Wh/kg Energy/size 60-75 Wh/L Power/weight 180 W/kg Charge/discharge efficiency 70%-92% Energy/consumer-price 7(sld)-18(fld) Wh/US$ [1]
Self-discharge rate 3%-20%/month [2]
Time durability 6 months
Cycle durability 500-800 cycles
Nominal Cell Voltage 2.0 V

Lithium-ion batteries [wikipedia.org]
Energy/weight 160 Wh/kg
Energy/size 270 Wh/L
Power/weight 1800 W/kg
Charge/discharge efficiency 99.9%[1]
• #### A123 competitors already on the market? (Score:3, Informative)

on Wednesday April 11, 2007 @05:21AM (#18686519) Homepage Journal
Nanoscale Lithium battery technology leads me to think A123 cells. The cell from this startup are already on the market, powering handheld screwdrivers and model airplanes. They use a patented LiFePo4 reaction(or was there some sulfur in it too, dunno) and their process is much more ideal for automotive transport than NiMH(not enough energy density) or LiPo(Lithium polymer, it's what's making laptops go up in flames the last few years). LiPo has the highest energy density, but is very unsafe when punctured in a crash(or when overcharged): all energy in them will release in a short time, possibly causing fire as the decomposing polymer inside escapes as a flammable gas. The other drawback is that they have a very short lifespan: Max 500 charge-cycles (better count on 100-200) or 3 years (cells degenerate even when not in use). Thus far LiPo cells are prohibitively expensive, and no hybrid owner would like to fork over a few K every year for new batteries.
the A123 process is much more resilient wrt to abuse: you can run them down completely unlike LiPo or lead-acid, the stand overcharging much better, and if punctured they don't go up in flames. The company rates their cells as being able to deliver 2000 cycles, which is much more than lipo, NiMH, NiCad or Lead-acid.
And as far as I know, they have no ties to Delft University, but I have not read TFA yet...
They are here [a123systems.com].
• #### Re: (Score:2)

LiPo(Lithium polymer, it's what's making laptops go up in flames the last few years). LiPo has the highest energy density, but is very unsafe when punctured in a crash(or when overcharged)

You must be thinking of Li-Ion. Li-Ion uses a flammable organic solvent as the electrolyte, while Li-Po uses a salt held in a solid non-flammable polymer. Li-Ion is usually used for higher-current applications like laptop computers, while Li-Po is usually used in low-current applications like mobile phones. The exploding laptops used Li-Ion batteries.

• #### They're not the only ones... (Score:3, Informative)

on Wednesday April 11, 2007 @05:34AM (#18686551)
Toshiba announced [technewsworld.com] research on a technology for fast charging li-ions over two years ago. This was using nanotech materials for an improved anode (maybe cathode too), enabling fast charging (80% charge in one minute) and long life (99% capacity after 1,000 charges). A similar approach [newscientist.com] was also annouced, about the same time, by Altair Technologys in Reno. It's all about increasing the effective surface area of the anode, and perhaps making it from stronger stuff.

In traditional Li-ion cells, a big wear factor is that the anode can form a parasitic battery with the electrical contact, causing the terminal to eventually wear out, faster as you approach full cycling the battery. Heat is also a factor, in both terminals and the full cell... the higher internal resistance of the Li-ion vs. NiMH (or better still, NiCAD) limits peak power, and also increases the risk of damage or, particularly in quesitonably made cells, explosions.

Dramatic improvements in both of these are necessary to enable practical (in a commerical sense) pure electric vehicles (BEV). There's no conspiracy necessary... traditional NiMH cells are a problem for full electrics.. which the actual reason none of these cars have been successful. Not to mention the expense... the Toyota EV-RAV4, for example, cost \$42,000 and gave you about 100 miles on a charge.. and that with Toyota still selling them at a loss (as they did in the early days of the Prius, too).

In a hybrid, the batteries are only partially cycled (my 2003 Prius runs the NiMH cells over 40% of their capacity range; Toyota extended this to about 60% on the models starting in 2004), and that keeps them very long lived. Natrually, better batteries make a better hybrid, but the fact my Toyota can only go about 2-3 miles on a full charge doesn't impact its general use; the issues around battery technology today make the BEV a small niche product.

But the energy density is just too low even full cycling NiMH to make a BEV with mass appeal... most people would demand at least 200-300 miles of range, charging times on-the-road similar to that of petrol fueling (not the minimum of 15-30 minutes you'll have with today's cells), and long life (full cycling NiMH, they're good for about 500-1000 charges).

Once you have a higher density cell that doesn't wear out and can be charged in under 5 minutes, full EVs will be practical enough for a mainstream automaker to POSSIBLY launch a full production car, not just an experiment. This is critical technology for improving hybrids as well, and keep in mind that all practical FCEVs will also be hybrids (fuel cells suck at peak power demands, they like to be slow and steady, so you need a battery or supercapacitor to enable the peaks).
• #### Just one small technical problem (Score:4, Insightful)

on Wednesday April 11, 2007 @06:50AM (#18686903)
Have you considered the electrical power needed to charge a practical vehicle cell in 5 minutes?

Let's assume an average cruising consumption of about 15kw for a small car. At 60mph with a 300 mile range, that's 75kwh. To charge those cells in 5 minutes, assuming an 80% efficiency, will need 75 * 12 * 1.25 =~ 1.1 Megawatts. At 440V, even with a 3-phase charger, that's over 1000 amps. At 11KV it's a more reasonable 100A, but the weight of the inverter gear and the shielded connector in the car is considerable and you are going to spend rather more than 5 minutes padlocking the interlocks and cross checking before and after charge. At 440V the main issue will be the weight of the cables. Three cores of around 400mm cross section each are rather heavy.

It's possible to imagine a world in which fuel stations supply exchange cells, but given the natural nervousness of most drivers when close to empty, it's unlikely to be practical or cost effective.

The model is wrong. You have to imagine a world in which car parks have charging stations that charge at reasonable rates, as do hotels and houses. You will need a general beefing up of the electricity distribution network, and you will need plenty of nuclear, solar and wind energy sources. And people will have to plan maybe a little further ahead than they do at present. Long trips will mandate an overnight stop. Probably a good thing as the only accidents I have ever had were after driving too long in a day.

On that model with a more reasonable 10-hour charge, the necessary charging rate is about 9KW - still a heavy cable, but with a socket about the size and complexity of the sort used for portable machines in factories and for boat shorepower.

Just don't try to use your wind turbine. In our location, to run my small car on its current, fairly low usage cycle, I would need a 6M diameter turbine on a 40M pylon, and I suspect the neighbours would object.

• #### Re: (Score:2)

Just don't try to use your wind turbine. In our location, to run my small car on its current, fairly low usage cycle, I would need a 6M diameter turbine on a 40M pylon, and I suspect the neighbours would object.

That would be a very small turbine. Why not go for something like this one [vestas.com], 82m diameter with a 59m tower? That should power a few cars, and it's a good mid-size turbine for use in areas where you cannot depend on a strong, regular wind. Place it half a mile or more from houses, of course, otherwise
• #### Is lithium really the best idea for cars? (Score:2)

Lithium doesn't really pack *much* more energy density (in terms of volume), but does do it with less weight. That's terrific.

But while lithiums handle deep discharge much better than lead-acid batteries, they're still not as good as NiCad or NiMh. They're also a lot more expensive. And, probably the best argument against them... look at the fires that happen when laptop (or even CELL PHONE) lithium cells are damaged or shorted. Now, imagine a car packing a thousand times more getting in an accident...
• #### Shame on GM (Score:2)

Every time I read about improvements in traction batteries I get angry at the way they missed their opportunity. If they had just kept manufacturing the EV-1 and selling it to the long waiting list of buyers, they could be riding the wave of improving battery technology.

Probably 80% of the cars I see on the road during that drive are commuting less than a hundred miles round trip.

To date, I've seen exactly one EV-1 on the road.

It was about five years ago that I saw my first Prius on the road. It was two yea
• #### Re: (Score:2)

I recall walking along a street in LA back around 2000 or 2001 and in the corner of my eye I saw a silent car roll up on my left. I turned to look at what it was and saw it was an EV-1. It was beautiful, and broke my heart a little, since GM had already made it clear the EV-1 was on its way out.

I've got a fairly efficient 7 year old 2dr hatchback with manual transmission which I only drive for trips and groceries and the like ( since I walk to work ). It's got 55k miles on it, and my hope/goal is to put a

• #### Ultracaps a long way off, maybe never. (Score:2)

Every time a discussion on batteries comes up, someone brings up ultracapacitors as the savior wonder technology. Then they use power and energy densities interchangeably.

Power densities (KW/Kg) for electric cars are all but irrelevant for current technologies. All power density reflects is how fast you can discharge. For any battery containing sufficient energy density, there will be adequate power density. Any time you see power density being highlighted it is a red herring attempt to distract from the fa
• #### In The Next 5 Years (Score:2)

In the next 5 years. It's always in the Next 5 Years. I should live so long.

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